FROM THE EXPERTS

Getting to grips with the problem of dry eyes

PUBLISHED : Friday, 07 November, 2014, 5:23pm
UPDATED : Friday, 07 November, 2014, 5:23pm

The arrival of winter in Hong Kong brings with it a welcome change of climate. It means cooler temperatures and more pleasant weather conditions.

The cool winter season starts sunny in November and becomes cloudier towards February. That tends to be good news for most people. It is a time to be happy and enjoy the best time of the year. But for some it heralds the start of a period of extra suffering.

Dry eye syndrome - when the eyes do not make enough tears or the tears evaporate too quickly, causing inflammation and irritation - is a common problem worldwide and particularly affects people in Hong Kong, where the onset of drier weather in the winter months tends to aggravate the condition.

At some stage in our lives many of us have experienced discomfort and irritation associated with dry eyes.

Studies have shown that up to 30 per cent of Asians suffer from dry eye syndrome, compared to around just 10 per cent of people in the United States and Australia.

Furthermore, some medications, such as antihistamines, antidepressants, beta-blockers and oral contraceptives, may decrease tear production.

Symptoms include itchy and red eyes, a stinging and burning sensation that feels like having a speck of dust in the eye, the eyes feel tired easily, a secretion from the eyes and oversensitivity to light.

Other warning signs are an inability to wear contact lenses for a long time and the wearable time shortens, eye discomfort when reading or working on a computer, and unusual tear production.

Common causes among Hong Kong patients are related to excessive tear evaporation stemming from using computers and smartphones for long hours, which decrease the frequency of blinking. A normal person on average blinks 10 to 30 times per minute. When you use a computer, smartphones or read for a long time, your eyes will open up wider and blink merely several times a minute. Best practice is to take a break every 15 minutes to let the eyes rest.

Women who wear make-up need to ensure they cleanse and wash it off completely at night, taking care to clean the eyelids to prevent infection. Late nights and overconsumption of deep-fried food can also increase the risk of eyelid infection. Turning up air conditioners or using heaters for long periods during the winter removes a huge amount of moisture from the air and also causes excessive tear evaporation, triggering dry eyes.

In general, city folk have built unhealthy lifestyles for themselves. Add increased pollution levels and drier weather conditions and it is not hard to see why it is easier these days to develop dry eyes.

The problem of dry eyes is closely related to our lifestyle. Staying indoors in an air-conditioned environment and wearing contact lenses for long periods of time can also increase the risk of dry eyes. About half of the people who wear contact lenses complain of having dry eyes.

To prevent the problem we need to start changing our lifestyle. We need to ensure we generate enough tears to keep our eyes healthy. Tears lubricate our eyes and help us see things clearly. They also help with blinking. They prevent dryness and protect our eyes from irritants by coating the surface. It is vitally important that this occurs.

Another critical function of tears is that they supply oxygen and nutrients to the surface of our eyes.

But it doesn't end there. Tears also help prevent infection by washing out foreign bodies that get into the eyes. They also work to heal damage caused to the surface of the eyes.

So, it is important to protect your eyes. If you suffer from dry eyes you need to:

  • Get a doctor to diagnose the cause of dry eyes.
  • Avoid or reduce computer time.
  • Use artificial tears or lubricating gel.

Dr Jeff Hui is a Hong Kong-based ophthalmologist